feature #12884 [Docs] add registration/login examples (SirDomin, arti0090)

This PR was merged into the 1.11-dev branch.

Discussion
----------

| Q               | A
| --------------- | -----
| Branch?         | master
| Bug fix?        | no
| New feature?    | no
| BC breaks?      | no
| Deprecations?   | 
| Related tickets | 
| License         | MIT

<!--
 - Bug fixes must be submitted against the 1.9 or 1.10 branch (the lowest possible)
 - Features and deprecations must be submitted against the master branch
 - Make sure that the correct base branch is set

 To be sure you are not breaking any Backward Compatibilities, check the documentation:
 https://docs.sylius.com/en/latest/book/organization/backward-compatibility-promise.html
-->


Commits
-------

e4a968d07a [Docs] add registration/login examples
8e70b928e9 Document full checkout process

docs/getting-started-with-sylius/index.rst

@@ -41,6 +41,7 @@ and simplest way from an idea ("I want to sell some stuff online") to the first
     plugin-installation
     deployment
     summary
+    using-api
 
 .. include:: /getting-started-with-sylius/map.rst.inc
 

docs/getting-started-with-sylius/map.rst.inc

@@ -7,3 +7,4 @@
 * :doc:`/getting-started-with-sylius/plugin-installation`
 * :doc:`/getting-started-with-sylius/deployment`
 * :doc:`/getting-started-with-sylius/summary`
+* :doc:`/getting-started-with-sylius/using-api`

docs/getting-started-with-sylius/using-api.rst

@@ -0,0 +1,352 @@
+Using API
+=========
+
+Since sylius 1.8 we allow you to use our new API based on ApiPlatform.
+Here are some examples of basic usage for a shop implementation.
+
+Register a customer
+-------------------
+
+To register a customer all we need to do is a single `POST` request:
+
+.. code-block:: bash
+
+    curl -X 'POST' \
+        'https://master.demo.sylius.com/api/v2/shop/customers' \
+        -H 'accept: */*' \
+        -H 'Content-Type: application/ld+json' \
+        -d '{
+        "firstName": "shop",
+        "lastName": "user",
+        "email": "shop.user@example.com",
+        "password": "pa$$word",
+        "subscribedToNewsletter": true
+    }'
+
+If we get response code `204`, it means our customer has been registered successfully.
+
+.. image:: ../_images/sylius_api/api_platform_shop_customer_post.png
+
+Login to the shop
+-----------------
+
+Once the shop customer has been registered, we can now create a login request to get the authentication token, which will allow us to use more shop endpoints.
+To get this token, lets create a simple login request:
+
+.. code-block:: bash
+
+    curl -X 'POST' \
+        'https://master.demo.sylius.com/api/v2/shop/authentication-token' \
+        -H 'accept: application/json' \
+        -H 'Content-Type: application/json' \
+        -d '{
+        "email": "shop.user@example.com",
+        "password": "pa$$word"
+    }'
+
+.. image:: ../_images/sylius_api/api_platform_shop_customer_post.png
+
+As a response we should get code `200`, along with `token` and `customer` iri.
+
+.. code-block:: json
+
+    {
+        "token": "string",
+        "customer": "iri"
+    }
+
+.. note::
+
+    If your shop has been customized and user first need to authenticate by `email authentication`, the token won't be returned.
+
+With this token we are able to authenticate ourselves to use full `shop` potential of sylius API.
+
+.. code-block:: bash
+
+    curl -X 'METHOD' \
+        'api-url' \
+        -H 'accept: application/ld+json' \
+        -H 'Authorization: Bearer token'
+
+Utilising most typical operations
+---------------------------------
+
+With our customer created and authorized we are now ready to use our shop API. As we are in world of e-commerce,
+there should be no doubt that most important operations are related with products, carts and orders.
+In this chapter of `Using API` we will get to know with these operations on API.
+
+Adding product to cart
+----------------------
+
+Let's make a simple process of checking out in shop API, it is possible to complete it as guest (not authenticated customer)
+or as authorized shop user. For example purposes we will use the logged in shop user.
+
+First step is to pickup a new cart:
+
+.. code-block:: bash
+
+    curl -X 'POST' \
+      'https://master.demo.sylius.com/api/v2/shop/orders' \
+      -H 'accept: application/ld+json' \
+      -H 'Content-Type: application/ld+json' \
+      -H 'Authorization: Bearer token' \
+      -d '{
+            # "localeCode": "string" (optional)
+        }'
+
+.. note::
+
+    You can checkout your cart in different locale if needed. If no `localeCode` is provided, the channels default will be added automatically.
+
+As a response we should get code `201`, along with default cart values and `tokenValue` which we need for next operations.
+
+.. image:: ../_images/sylius_api/api_platform_shop_orders_post.png
+
+Now let's add some product to this cart, first we need the ProductVariant IRI, we can get some of the variants from
+
+.. code-block:: bash
+
+    curl -X 'GET' \
+      'https://master.demo.sylius.com/api/v2/shop/product-variants?page=1&itemsPerPage=30' \
+      -H 'accept: application/ld+json' \
+      -H 'Authorization: Bearer token'
+
+and let's take first variant `@id` from list:
+
+.. code-block:: bash
+
+    # ...
+    {
+      "@id": "/api/v2/shop/product-variants/Everyday_white_basic_T_Shirt-variant-0",
+      "@type": "ProductVariant",
+      "id": 123889,
+      "code": "Everyday_white_basic_T_Shirt-variant-0",
+      "product": "/api/v2/shop/products/Everyday_white_basic_T_Shirt",
+      "optionValues": [
+        "/api/v2/shop/product-option-values/t_shirt_size_s"
+      ],
+      "translations": {
+        "en_US": {
+          "@id": "/api/v2/shop/product-variant-translation/123889",
+          "@type": "ProductVariantTranslation",
+          "id": 123889,
+          "name": "S",
+          "locale": "en_US"
+        }
+      },
+      "price": 6420,
+      "originalPrice": 6420,
+      "inStock": true
+    }
+    # ...
+
+Then going back to cart - let's add the variant to our cart with:
+
+.. code-block:: bash
+
+    curl -X 'PATCH' \
+      'https://master.demo.sylius.com/api/v2/shop/orders/rl1KwtiSLA/items' \
+      -H 'accept: application/ld+json' \
+      -H 'Authorization: Bearer token' \
+      -H 'Content-Type: application/merge-patch+json' \
+      -d '{
+      "productVariant": "/api/v2/shop/product-variants/Everyday_white_basic_T_Shirt-variant-0",
+      "quantity": 1
+    }'
+
+.. image:: ../_images/sylius_api/api_platform_shop_orders_items_patch.png
+
+And after this call the response should has code `200`, and in body we can see that the product variant has been added:
+
+.. code-block:: bash
+
+    {
+      # Rest of orders body
+      "items": [
+        {
+          "@id": "/api/v2/shop/order-items/59782",
+          "@type": "OrderItem",
+          "variant": "/api/v2/shop/product-variants/Everyday_white_basic_T_Shirt-variant-0",
+          "productName": "Everyday white basic T-Shirt",
+          "id": 59782,
+          "quantity": 1,
+          "unitPrice": 6420,
+          "total": 6869,
+          "subtotal": 6420
+        }
+      ],
+      # Rest of orders body
+    }
+
+Changing product quantity
+-------------------------
+
+In this example we will use the product variant from example above. We will change the quantity of this item.
+We need from the last response an `id` of product variant (it is 59782 in this example). Let's populate the
+fields needed for request and call it:
+
+.. code-block:: bash
+
+    curl -X 'PATCH' \
+      'https://master.demo.sylius.com/api/v2/shop/orders/OPzFiAWefi/items/59782' \
+      -H 'accept: application/ld+json' \
+      -H 'Authorization: Bearer token' \
+      -H 'Content-Type: application/merge-patch+json' \
+      -d '{
+      "quantity": 3
+    }'
+
+.. image:: ../_images/sylius_api/api_platform_shop_orders_change_quantity.png
+
+And the response should return status code `200` and in items, the quantity as well as total price of this product variant should be changed:
+
+.. code-block:: bash
+
+    {
+      # Rest of orders body
+      "items": [
+        {
+          "@id": "/api/v2/shop/order-items/59782",
+          "@type": "OrderItem",
+          "variant": "/api/v2/shop/product-variants/Everyday_white_basic_T_Shirt-variant-0",
+          "productName": "Everyday white basic T-Shirt",
+          "id": 59782,
+          "quantity": 3,
+          "unitPrice": 6420,
+          "total": 19538,
+          "subtotal": 19260
+        }
+      ],
+      # Rest of orders body
+    }
+
+.. image:: ../_images/sylius_api/api_platform_shop_orders_change_quantity_response.png
+
+Completing the order
+--------------------
+
+So, we have our cart with items that we want to buy. Let's finish our order by completing and placing it.
+There are just few more steps to do it:
+
+**1.** Addressing order
+
+.. code-block:: bash
+
+    curl -X 'PATCH' \
+      'https://master.demo.sylius.com/api/v2/shop/orders/rl1KwtiSLA/address' \
+      -H 'accept: application/ld+json' \
+      -H 'Authorization: Bearer token' \
+      -H 'Content-Type: application/merge-patch+json' \
+      -d '{
+        "email": "shop.user@example.com",
+        "billingAddress": {
+            "city": "California",
+            "street": "Coral str",
+            "postcode": "90210",
+            "countryCode": "US",
+            "firstName": "David",
+            "lastName": "Copperfield"
+        }
+    }'
+
+.. image:: ../_images/sylius_api/api_platform_shop_orders_addressing.png
+
+.. note::
+
+    The shippingAddress field is optional - if no shippingAddress is provided the field will be cloned from billingAddress
+
+Which will response with addressed cart:
+
+.. image:: ../_images/sylius_api/api_platform_shop_orders_addressing_response.png
+
+**2.** Selecting Shipping/Payment Method
+
+In case of both shipment and payment first we need to get their corresponding `id` and `method`.
+
+We can get it from the address response or call once again all data about order by calling:
+
+.. code-block:: bash
+
+    curl -X 'GET' \
+  'https://master.demo.sylius.com/api/v2/shop/orders/rl1KwtiSLA' \
+  -H 'accept: application/ld+json' \
+  -H 'Authorization: Bearer token'
+
+In response we need to find payment and shipment where everyone of them has the required fields.
+
+.. code-block:: bash
+
+    "payments": [
+        {
+          "@id": "/api/v2/shop/payments/20446",
+          "@type": "Payment",
+          "id": 20446,
+          "method": "/api/v2/shop/payment-methods/cash_on_delivery"
+        }
+    ],
+    "shipments": [
+        {
+          "@id": "/api/v2/shop/shipments/17768",
+          "@type": "Shipment",
+          "id": 17768,
+          "method": "/api/v2/shop/shipping-methods/ups"
+        }
+    ],
+
+Let's make a shipment in this example. The required fields are `shipmentId` in URL query and `shipmentMethod` IRI in body:
+
+.. code-block:: bash
+
+    curl -X 'PATCH' \
+      'https://master.demo.sylius.com/api/v2/shop/orders/rl1KwtiSLA/shipments/17768' \
+      -H 'accept: application/ld+json' \
+      -H 'Authorization: Bearer token' \
+      -H 'Content-Type: application/merge-patch+json' \
+      -d '{
+      "shippingMethod": "/api/v2/shop/shipping-methods/ups"
+    }'
+
+.. image:: ../_images/sylius_api/api_platform_shop_orders_choose_shipping.png
+
+which should respond with `200` status code and data about order.
+
+And for the `Payment` the process is the same just change the:
+
+#. Endpoint `api/v2/shop/orders/tokenValue/shipments/shipmentId` => `api/v2/shop/orders/tokenValue/payments/paymentId`
+#. Body `shippingMethod` => `paymentMethod` (with method from possible payments)
+
+Now with all the data fulfilled, let's proceed to last step.
+
+**3.** Completing Cart
+
+This is the last step of checkout process. Just simply call this endpoint and if you want, you can add a note to your order:
+
+.. code-block:: bash
+
+    curl -X 'PATCH' \
+      'https://master.demo.sylius.com/api/v2/shop/orders/rl1KwtiSLA/complete' \
+      -H 'accept: application/ld+json' \
+      -H 'Authorization: Bearer token' \
+      -H 'Content-Type: application/merge-patch+json' \
+      -d '{
+      "notes": "your note"
+    }'
+
+.. image:: ../_images/sylius_api/api_platform_shop_orders_completed.png
+
+It will respond with `200` status code and data about order where `checkoutState` should be changed to `completed`:
+
+.. code-block:: bash
+
+    {
+        # Orders body
+        "currencyCode": "USD",
+        "localeCode": "en_US",
+        "checkoutState": "completed",
+        "paymentState": "awaiting_payment",
+        "shippingState": "ready",
+        # Orders body
+    }
+
+And here we go - full checkout process completed with new API on Sylius. With this basic usage you should be able to
+create fully functional shop frontend based on Sylius backend and logic.